Power transmission device



1940- H. FijTTlNGER 2,226,750

POWER TRANSMISSION DEVICE Filed NOV. 18, 1958 Inyekflor Hermann F ahinger, by W 5 fl w/m/ His Afrorney Patented Dec. 31, 1940 PATENT OFFICE POWER TRANSMISSION DEVICE Hermann Fiittinger, Berlin-Charlottenburg, Germany Application November 18, 1938, Serial No. 241,275 In Germany November 19, 1937 2 Claims.

My invention relates to power transmission devices, and more particularly to a power transmission device comprising a mechanical gear train and a hydraulic gear. The mechanical gear 5 train illustratedand described in this application is a standard form of 'an epicyclic gear train whereby power from a driving member is divided and transmitted to a driven member through two channels, one channel being a direct mechanical connection and the other channel being through 1 the hydraulic gear. The hydraulic gear may be a coupling consisting of a pump wheel and a turbine wheel, ora torque converter comprising besides the pump wheel and the turbine wheel a guide wheel. This-type of hydraulic gear is described in greater detail in U. S. Patents 1,199,359 and 1,199,361, issued to Fottinger.

One object of my invention is the provision of greater flexibility, and to reduce losses, in

power transmissions of this type.

For further objects and advantages of my invention reference is had to the following specification when taken in connection with the accom- 25 panying drawing, and its scope will be pointed out in the accompanying claims.

The accompanying drawing illustrates, in Fig. 1, a vertical cross-section of a power transmission device embodying my invention.-

30 Referring to the drawing, the driving shaft I projects into a housing I" in which it expands into a disk I" which carries several pins 2. The pins 2 are equally spaced about the axis of the shaft I and carry respectively planet gears 3 and 35 3, engaging the toothed outer ring-gear, or orbit gear, 3 which is attached to the Wall of the housing I. The housing I is rigidly connected to the turbine wheel of the hydraulic coupling. The planet gears also engage a sun gear '6 40 mounted on a connecting shaft 7.. This shaft I is supported at one end'in a bearing I provided in the end of shaft I and carries on its grooved part 8 one or more clutch plates 9 engaging with similar plates I0 fixed by grooves to the pump 45 wheel II of the hydraulic coupling. The plates may be pressed together in any way known for such clutches, for instance by hydraulic means consisting of .a'piston I2, comprising a ring, or disk, axially movable on the shaft I and inside 5 of the cylindrical space I3 provided in the hub of the pump wheel II. Oil for moving the piston I2 is supplied to the space I3 through oil ducts I4, I5 and I6. Oil duct I4 is in the shaft 1. Oil duct I5 is provided in a member I5 which is 55 attached to the pump wheel I I to close the space I3 in the hub of the pump wheel. This member I5 is provided with a shaft extension I5" for supporting the pump wheel. The shaft extension I5" of member I5 rests in a bearing provided in a shaft 20 and in a disk 20', the disk 20' 5 being integral with the shaft .20 and also attached to the casing I9. Oil reaches the duct I5 through the duct I6 in the shaft '20 from a sleeve ll surrounding the shaft 20 and provided with an annular channel II. This annular channel is 1 supplied with oil through an oil pipe I8. The oil ducts may also lead through the left side of the shaft I and through the shaft I, as indicated by dotted lines. The casing I9 of the hydraulic coupling connects the turbine wheel 5 with the driven shaft 20.

The operation is as follows:

The shaft I drives the planet gears 3, 3, from which the power is divided and transmitted in one channel through the toothed rim 4, fixed to the turbine wheel 5, the casing I9 to the driven shaft 20, and in another channel through the sun gear 6, the shaft of which in ordinary service is connected by the clutch plates 9 and II) to the pump wheel II, circulating oil or water through the turbine 5 and back through II in the sense of the arrows. In such a way one part of power is transmitted mechanically from shaft I to shaft 20, while another part is transformed first into hydrokinetic energy and then added to the mechanically transmitted power.

When the driven shaft 20 and the toothed rim 4 however are kept stationary, the epicyclic gear tends to impart a considerably increased speed to the pump wheel I I. I This would cause a strong ventilation, if the hydraulic coupling were emptied, or an enormous increase of primary and secondary power, if the hydraulic coupling remains filled. 40

By closing and opening the clutch in the described manner difliculties and losses are avoided, so that the driven shaft 20 can be freed of substantially all torque thus allowing an easy shifting of any toothed change gear interposed betwee'n'the shaft 20 and the driven member (machine, axle). In the known combinations of a hydraulic coupling and a mechanical clutch the latter must be built for the full power transmitted from the inlet to the outlet shaft, while my invention necessitates a clutch of one fourth or fifth only, of that capacity, in the hydrokinetic channel of the power transmission,- the larger mechanical power transmission remaining unchanged, i. e. without detachable means.

' What I claim. as. new. and desire to secure by Letters Patentor the United Btetes'isr' 1. In a. power transmission device, the combination of a .drivesmitten epicyclic gearingcomprisingi a sun efllvanprbit gear and planetgeers, a. support for said planet gears attached to said drive shaft, a hydraulic coupling having a turbine wheel and an impeller wheel, one of said wheels being connected to said orbit gear, and a clutch operable to connect and to disconnect said sun gear and the other 01' said hydraulic coupling wheels.

2. In a power transmission device. the combinationoi ,drive ,shsft, en epicyciic, gearing comprising a sun gear, an orbit-gesrsndlil t 

